Question

Sa se determine inversul numarului complex:
Z1=1+2i

Answer 1

$\frac{1}{z_{1}} =^{1-2i)} \frac{1}{1+2i} = \frac{1-2i}{1^2-4i^2}= \frac{1-2i}{5}= \frac{1}{5} - \frac{2}{5} i$